BEIRUT, April 9 (Reuters) - Forces loyal to President Bashar al-Assad advanced into the rebel-held Syrian border town of Rankous on Wednesday, consolidating their control over a former rebel supply line from neighbouring Lebanon.

The assault on Rankous is the latest stage of an offensive by the army and Hezbollah fighters to seal off the border region and secure the main highway leading north from Damascus towards central Syria, Homs, and the Mediterranean coast.

Hezbollah's television channel Al-Manar said Rankous was under complete control of Assad's forces, but Syrian state television and the Syrian Observatory for Human Rights monitoring group said fighting continued on the edges of town.

"Units of the Syrian Arab Army are advancing in Rankous and are pursuing the remnants of the terrorists groups on its northern fringes and the surrounding farmlands," Syrian television said.

The fight for Rankous takes place less than a month after Hezbollah and the Syrian army recaptured the rebel stronghold of Yabroud, choking off the vital supply line into central Syria.

Backed by Shi'ite fighters from Hezbollah and Iraq as well as Russian weapons and Iranian military commanders, Assad has regained territory around Damascus and central Syria leading to the coastal strongholds of his Alawite minority.

But the mainly Sunni Muslim rebels and foreign jihadi fighters still control most of eastern Syria and the north, and are fighting Assad's forces in north of the coastal province of Latakia. (Reporting By Dominic Evans; Editing by Angus MacSwan)